I just read the entire Federal US Code. There is no more mention of it being unlawful to manufacture destructive devices if you get a license.

But it is now illegal to manufacture and posses semiatuomatic weapons (aka AR-15's).??

"(v)(1) It shall be unlawful for a person to manufacture, transfer, or possess a semiautomatic assault weapon. (2) Paragraph (1) shall not apply to the possession or transfer of any semiautomatic assault weapon otherwise lawfully possessed under Federal law on the date of the enactment of this subsection. (3) Paragraph (1) shall not apply to - (A) any of the firearms, or replicas or duplicates of the firearms, specified in Appendix A to this section, as such firearms were manufactured on October 1, 1993; (B) any firearm that - (i) is manually operated by bolt, pump, lever, or slide action; (ii) has been rendered permanently inoperable; or (iii) is an antique firearm;

(C) any semiautomatic rifle that cannot accept a detachable magazine that holds more than 5 rounds of ammunition; or (D) any semiautomatic shotgun that cannot hold more than 5 rounds of ammunition in a fixed or detachable magazine."

The only law that affects machine guns would be the law that says

"(4) for any person, other than a licensed importer, licensed manufacturer, licensed dealer, or licensed collector, to transport or sell in interstate or foreign commerce any destructive device, machinegun (as defined in section 5845 of the Internal Revenue Code of 1986), short-barreled shotgun, or short-barreled rifle, except as specifically authorized by the Attorney General consistent with public safety and necessity;"